Частота и быстродействие спинового вентиля с планарной анизотропией слоев

The dynamics of the magnetization vector in the free layer of a layered spin-valve structure was simulated. As materials for the free and fixed layers, six magnetically soft ferromagnets with longitudinal anisotropy were considered. The types of magnetization dynamics that are of practical interest for MRAM and HMDD (switching of the magnetization vector), STNO (stable precession of the magnetization vector), and the base element PSL (switching of the magnetization vector with two probable outcomes) were highlighted. The ranges of currents and fields corresponding to these operating modes of the spin valve were calculated. The numerical calculations of the switching time showed that, among the considered materials for the MRAM cell, the most suitable is Co80Gd20 alloy, while for the HMDD read head, it is Fe60Co20B20. As a result of the precession frequency calculations, it was concluded that the Fe60Co20B20 alloy is optimal for the STNO ferromagnetic layers. For the implementation of PSL, the best switching characteristics were demonstrated by the Co93Gd7 alloy.

Critical switching characteristics of three-layered spin valve for different materials and alloys with uniaxial anisotropy

We analyze the dependence of the current density and magnetic field switching on the magnetic parameters of the material of the ferromagnetic layers of the spin valve. Comparison of critical characteristics of the spin valve with longitudinal anisotropy of ferromagnetic layers fabricared of different materials showed that the promising materials for the fabrication of spin valve are cobalt, iron, their alloys, ferroborates of cobalt and alloys of cobalt with gadolinium. For these materials we produced and analyzed the bifurcation diagrams of equations describing the switching process of the spin valve. Based on the study of the dynamics of the magnetization vector we obtained the numerical evaluation of time switching.